An oil company has taken out full-page ads in some Canadian newspapers to apologize for the deaths of 500 ducks at an Alberta oilsands plant.

The open letter-style ads, which are signed by Syncrude Canada CEO Tom Katinas, appear in the Alberta editions of several newspapers.

Syncrude Canada owns the waste-filled tailings pond where the oil-coated ducks were found earlier this week. The pond is filled with waste from Syncrude's oilsands operation at the Aurora North Site mine, north of Fort McMurray.

Of the roughly 500 ducks that landed on the pond, only five were rescued. Company officials acknowledge more ducks landed on the pond but flew away.

In Saturday's newspaper ad, Syncrude says it's committed to making sure such a "sad event" doesn't happen again.

The company, the largest oilsands operation in the world, says it will learn from what happened, will improve its practices and will meet the public's expectations for "responsible development."

The ad also says the company is co-operating with authorities.

Prime Minister Stephen Harper on Thursday said Ottawa would investigate the deaths of the ducks.

Greenpeace called the apology "hollow," saying it expects a firm commitment from the company to change its practices.

"Syncrude placing ads definitely means that they're feeling the public pressure now that the public has images of just how huge and massive these toxic tailings lakes are, and what the extent of the damage is," Greenpeace activist Mike Hudema said. "This isn't an isolated incident."

Members of the environmental organization plan to go to the Alberta legislature Monday to demand the government impose stricter regulations on the oilsands industry.

With files from the Canadian Press